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The Xinjiang region of China is among the most sensitive regions to global warming. Based on the meteorological and hydrological observation data, the regional wet-to-dry climate regime shifts in Xinjiang were analyzed and the impacts of climatic shift on the eco-hydrological environment of Xinjiang were assessed in this study. The results showed that temperature and precipitation in Xinjiang have increased since the mid-1980s, showing a warming-wetting trend. However, drought frequency and severity significantly increased after 1997. The climate of Xinjiang experienced an obvious shift from a warm-wet to a warm-dry regime in 1997. Since the beginning of the 21st century, extreme temperatures and the number of high temperature days have significantly increased, the start date of high temperature has advanced, and the end date of high temperature has delayed in Xinjiang. In addition, the intensity and frequency of extreme precipitation have significantly increased. Consequently, regional ecology and water resources have been impacted by climatic shift and extreme climate in Xinjiang. In response, satellite-based normalized difference vegetation index showed that, since the 1980s, most regions of Xinjiang experienced a greening trend and vegetation browning after 1997. The soil moisture in Xinjiang has significantly decreased since the late 1990s, resulting in adverse ecological effects. Moreover, the response of river runoff to climatic shift is complex and controlled by the proportion of snowmelt to the runoff. Runoff originating from the Tianshan Mountains showed a positive response to the regional wet-to-dry shift, whereas that originating from the Kunlun Mountains showed no obvious response. Both climatic shift and increased climate extremes in Xinjiang have led to intensification of drought and aggravation of instability of water circulation systems and ecosystem. This study provides a scientific basis to meet the challenges of water resource utilization and ecological risk management in the Xinjiang region of China.

Climate change threatens species adapted to cool alpine environments, particularly ectotherms like reptiles. Small-sized grassland specialist vipers inhabit such environments in Eurasia and are highly susceptible to overheating and dehydration as global temperature rises. This study modelled activity restriction times, defined as hours when environmental temperatures exceed the thermal tolerance (i.e. not available for essential activities) of the species, for 20 grassland viper taxa to assess climate change impacts. Under future conditions, hours of activity restriction are projected to increase by 21% by the SSP1-2.6 scenario, and by 52.1% by the SSP5-8.5 scenario. Elevation and latitude significantly influenced restriction time changes, with high-altitude and northern populations predicted to be most affected. The taxa Vipera graeca and Vipera ursinii moldavica are expected to experience the greatest increase in restriction times. Despite warmer conditions potentially increasing hours within preferred thermal ranges, vipers are unlikely to exploit lower-elevation habitats due to competition and ecological constraints. These findings emphasise the urgent need for conservation strategies, including habitat preservation and connectivity, to mitigate the adverse effects of climate change on grassland vipers, particularly the most vulnerable populations.

The proposed cosmic-induced conflagration of the black mat (BM), at the end of the Allerød interstade, dated to the 12.8 ka—Younger Dryas boundary (YDB), has been variably related to multiple airburst events following earth’s encounter with the Encke Comet. Evidence for the BM, as on Mt. Viso in the Western Alps of Europe, and in the high northwestern Venezuelan Andes, relies upon variably distributed rock clasts, paleosols, and sediment resident in Late Glacial (LG) moraines, mass wasted deposits, and glaciolacustrine sediment. It is the age correlation of these two cosmic-affected sites—Viso–Andes—correlated with the 12,737 ± 41 cal yr BP upper YD age glaciolacustrine sediment of Kråkenes, Norway, and readjused pollen sites to 12,820 yr BP that has not been discussed in terms of contemporaneity—cosmic–terrestrial. The cosmic theory termed the YD impact hypothesis—YDIH—has witnessed slow acceptance by the scientific community, compared with century-long attention paid to the YD terrestrially oriented hypotheses. The cosmic-affected LG sediment (Viso), with AMS C14 dated glaciofluvial sediment in the northern Andes, place the upper YD aligned with black mat dated sediment on several continents. As well, the cosmic hypothesis supporting the YD covers wider spatial ground compared with terrestrial arguments and is likely a progenitor of this one major climatic shift of the Neogene. Previous workers on the YD climatic shift, as outlined here, may have overlooked, or overreached to explain, the BM occurrence. Firming up the YDIH to the YDB parallels similar past struggles with continental drift to plate tectonics, crater age chronology theories on Mars, Agassiz’s ice age theory, and human-induced climatic warming. Time perhaps, to bring the terrestrially driven explanation for the YDB to the YDIH, the latter was continually supported by a number of independent studies.

Available ecological information, an extensive distributional range, conflicting osteological data, and a proposed early Miocene origin provide the impetus for the present study which investigates genetic structuring, biogeographic, and phylogenetic relationships within the Aplocheilichthys spilauchen lineage. Through the analysis of the mitochondrial gene COI, species delimitation methods (ABGD, GB, GMYC, bPTP) were applied, recognizing 6–7 OTUs with absolute pairwise genetic distances ranging between 8 and 22%. The onset of diversification is estimated to be within the middle Miocene and both dispersal and vicariance-shaped A. spilauchen diversity and distribution, as suggested by time-calibrated and ancestral range reconstruction (S-DIVA) analyses. We report for the first time, a pattern of diversification within a lineage of brackish water fish that is concordant with the historical distribution of coastal mangroves forests, shaped by a series of historical events that likely affected forest cover since the middle Miocene (e.g. major climate shifts and sea-level fluctuations, onset of the modern Congo River outlet, increased volcanism in the Cameroon Volcanic Line).

Global warming is one of the most pressing challenges of our time, contributing to climate change effects and with far-reaching implications for built environments. The main aim of this study is to assess the extent to which Annaba city, Algeria, as part of the Mediterranean region, is affected by global climate change and its broader influences. The study investigated climatic shifts in Annaba city, using a multi-step methodology integrating data collection and analysis techniques. Data collection included 23 years of climate data (2000–2023) from Annaba’s meteorological station, on-site measurements of microclimatic variations, and a questionnaire survey. The collected data underwent four main analyses: a time series analysis to describe climate parameters over 23 years, a statistical analysis to predict potential future climatic conditions (2024–2029) and the correlation of various climatic variables using specialized bioclimate tools to highlight seasonal variability, a spatial study of the urban heat island (UHI) phenomenon and perceived climatic shifts, and an analysis of extreme weather events characterizing heat atmospheric events in the context of urban climate change in the Mediterranean region. The findings revealed a consistent warming trend in Annaba city, with prolonged extreme climate conditions observed, particularly in the last four years (2020–2023). Significant temperature fluctuations were emphasized, notably in July 2023, with record-breaking maximum temperatures reaching 48.2 °C, the hottest on record with an increase of 3.8 °C, and presenting challenges amplified by the urban heat island effect, causing temperature differentials of up to 6 °C within built-up areas. Projections for 2029 suggest a tendency towards heightened aridity with a significant shift towards a new climate seasonality featuring two distinct main seasons—moderate and hot challenging. The abrupt disruption of calm weather conditions in Annaba on 24 July 2023 highlighted the influence of atmospheric circulation within the Mediterranean region featured for both anticyclones and atmospheric blocking phenomena on local weather patterns.

The lignicolous saprotrophic genus Entonaema contains six formally accepted species: E. liquescens (type species), E. cinnabarinum, E. globosum, E. dengii, E. moluccanum, and E. siamensis. Its stromatic ascomata develop on the surface of dead wood remnants; they are rather large, globose to irregularly shaped, and vividly coloured. The fresh stroma interior is filled with a liquid matter. In early studies, the genus was considered to have a preference for tropical habitats, while in more recent field research, numerous collections have been added from warm, temperate areas of Europe, North America, and Asia. Our taxonomic and phylogenetic studies were based on freshly collected E. cinnabarinum from Croatia and E. liquescens from the USA. A phylogenetic study of the sequence alignment of four concatenated gene regions (ITS, LSU, rpb2, and β-tub) revealed the true taxonomic position of Entonaema within Hypoxylaceae (Xylariales), a sister to Hypoxylon carneum. Detailed macroscopic and microscopic descriptions of E. cinnabarinum are accompanied by drawings and colour photographs, while the study of E. liquescens is focused on stromatal microchemical reaction. With new information, the worldwide identification key to the putative species of Entonaema is proposed. Ecological data and biogeographical patterns were studied using all available and reliable sources of recorded data. Climatic preferences of the two most widespread Entonaema species, E. liquescens and E. cinnabarinum, are discussed in detail.

Subtropical islands are often viewed as refuges where Quaternary climatic shifts driving global episodes of extinction were buffered. Island biodiversity, however, may have been impacted by climatic fluctuations at local scales, particularly in spatially heterogeneous island systems. In this study, we generated a conceptual framework for predicting the potential impact of Pleistocene extinctions on the biogeographical pattern of the Canarian spermatophyte flora, with a focus on the easternmost Canarian islands (ECI). Then, we performed an exhaustive bibliographic revision (270 studies) to examine whether taxonomic, phylogenetic and phylogeographical data support our predictions. Although molecular information is limited for many lineages, the available data suggest that the majority of extant ECI plant taxa may be the result of relatively recent (<1 Ma) dispersal from surrounding insular and mainland areas. Different lines of evidence are compatible with the idea of a Pleistocene period of frequent lineage extirpation on ECI. Extinction may thus have provided new ecological opportunities for recent (re)colonization, with some cases of recent establishment mediated by facilitation. Considering background extinction on ECI, we describe five general patterns of colonization for Canarian plant lineages. In addition to factors related to island ontogeny and long-distance dispersal, we suggest that Pleistocene extinctions may have significantly contributed to extant biogeographical patterns in the Canarian archipelago, such as the biased distribution ranges of island plants and the low endemic richness on ECI. This new scenario provides testable hypotheses for future studies dealing with the phylogeography, taxonomy and conservation of terrestrial biodiversity on the Canarian islands, and possibly, on other near-shore islands.

Understanding of the processes of divergence and speciation is a major task for biodiversity researches and may offer clearer insight into mechanisms generating biological diversity. Here, we employ an integrative approach to explore genetic and ecological differentiation of and distributed allopatrically along the two sides of the biogeographic boundary 'Tanaka Line' in Southwest China. We addressed these questions using ten low-copy nuclear genes and nine plastid DNA regions sequenced among individuals sampled from 28 populations across their geographic ranges in China. Phylogenetic, coalescent-based population genetic analyses, approximate Bayesian computation (ABC) framework and ecological niche models (ENMs) were conducted. We identified a closer phylogenetic relationship in maternal lineage of with than that between . and congeneric . A deep divergence between the two species was observed and occurred at the boundary between later Pliocene and early Pleistocene. However, the evidence of significant chloroplast DNA gene flow was also detected between the marginal populations of and . Niche models and statistical analyses showed significant ecological differentiation, and two nuclear loci among the ten nuclear genes may be under divergent selection. These integrative results imply that the role of climatic shift from Pliocene to Pleistocene may be the prominent factor for the divergence of . and . , and population expansion after divergence may have given rise to chloroplast DNA introgression. The divergence was maintained by differential selection despite in the face of gene flow.

Daily precipitation extremes are crucial in the hydrological design of major water control structures and are expected to show a changing tendency over time due to climate change. The magnitude and frequency of extreme precipitation can be assessed by studying the upper tail behavior of probability distributions of daily precipitation. Depending on the tail behavior, the distributions can be classified into two categories: heavy-tailed and light-tailed distributions. Heavier tails indicate more frequent occurrences of extreme precipitation events. In this paper, we have analyzed the temporal change in the tail behavior of daily precipitation over India from pre- to post-1970 time periods as per the global climatic shift. A modified Probability Ratio Mean Square Error norm is used to identify the best-fit distribution to the tails of daily precipitation among four theoretical distributions (e.g., Pareto-type II, Lognormal, Weibull, and Gamma distributions). The results indicate that the Lognormal distribution, which is a heavy-tailed distribution, fits the tails of daily precipitation for the majority of the grids. It is inferred from the study that there is an increase in the heaviness of tails of daily precipitation data over India from pre- to post-1970 time periods.

BACKGROUND AND AIMS: The genus Olea (Oleaceae) includes approx. 40 taxa of evergreen shrubs and trees classified in three subgenera, Olea, Paniculatae and Tetrapilus, the first of which has two sections (Olea and Ligustroides). Olive trees (the O. europaea complex) have been the subject of intensive research, whereas little is known about the phylogenetic relationships among the other species. To clarify the biogeographical history of this group, a molecular analysis of Olea and related genera of Oleaceae is thus necessary. METHODS: A phylogeny was built of Olea and related genera based on sequences of the nuclear ribosomal internal transcribed spacer-1 and four plastid regions. Lineage divergence and the evolution of abaxial peltate scales, the latter character linked to drought adaptation, were dated using a Bayesian method. KEY RESULTS: Olea is polyphyletic, with O. ambrensis and subgenus Tetrapilus not sharing a most recent common ancestor with the main Olea clade. Partial incongruence between nuclear and plastid phylogenetic reconstructions suggests a reticulation process in the evolution of subgenus Olea. Estimates of divergence times for major groups of Olea during the Tertiary were obtained. CONCLUSIONS: This study indicates the necessity of revising current taxonomic boundaries in Olea. The results also suggest that main lines of evolution were promoted by major Tertiary climatic shifts: (1) the split between subgenera Olea and Paniculatae appears to have taken place at the Miocene-Oligocene boundary; (2) the separation of sections Ligustroides and Olea may have occurred during the Early Miocene following the Mi-1 glaciation; and (3) the diversification within these sections (and the origin of dense abaxial indumentum in section Olea) was concomitant with the aridification of Africa in the Late Miocene.